vfio/iommu_type1: replace kvmalloc with kvzalloc and kfree with kvfree

virt inclusion
category: bugfix
bugzilla: https://gitee.com/openeuler/kernel/issues/I6FHYK


CVE: NA

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For security purposes, kvzalloc is used to allocate memory. Because
the memory may be allocated by vmalloc. So we replace kfree with
kvfree here.

Reported-by: Zhaolong Wang <wangzhaolong1@huawei.com>
Signed-off-by: Kunkun Jiang <jiangkunkun@huawei.com>
Reviewed-by: Keqian Zhu <zhukeqian1@huawei.com>
Signed-off-by: Jialin Zhang <zhangjialin11@huawei.com>